Certainly all presidents seek to undermine their opponents, but my sense of Bush has been that he has a take-no-prisoners style that I find repellant. For the most part, of course, this is a personal reaction, and is unlikely to be shared by his supporters.
Reading Kevin’s comments reminds me that many Democrats view Bush in almost the same way most Republicans viewed Bill Clinton. While I’ve always been able to intellectually grasp that Clinton was highly intelligent, generally disciplined politically, and had oratorical gifts, he just made my skin crawl. And this was true pre-Lewinsky; indeed, this reaction was there during the 1992 campaign. This is not a reaction I get to Democrats reflexively, including those far more ideologically different from me than Clinton. For reasons I don’t fully understand, many Democrats simply react to Bush in a very visceral manner. Certainly, the election controversy partly explains this, but the business about his stupidity and his “sneer” predated that.